1. Field of the Invention
This invention relates to excavating and construction equipment and more specifically to material handling systems for powered digging machines such as backhoes.
2. History of the Related Art
Backhoes have become some of the most commonly used equipment in modern industry. These machines are available in several mobile options, including track, wheel, rail, and barge mounted units. Foam filled tires, extendible dippers and side shift mounting arrangements are among the many options available for special applications.
With such a wide variety of jobs that must be done with a backhoe, it is sometimes difficult to avoid tying up a machine with specialized tools, such as log grapples and clamshell buckets, that require direct mounting to the dipper boom. Although these specialized tools work well, much time and labor are required in changing buckets and specialized tools. As a result, many machines are restricted from general use because of this disadvantage.
Several attachments are available that offer a partial solution to the problem of bucket and tool changing. These attachments are designed to aid in the handling of materials such as chunks of concrete, pipe, and logs, by providing a backup to the material being gripped by the curling action of the bucket. Some attachments also offer hydraulic control to the backup or clamping member to further help with the material handling.
Because of the similar mounting and operating action most of these attachments share, they tend to extend downward from the under side of the dipper boom excessively. This interferes with height clearance when working over obstacles such as high sided truck beds. Also, the material handling operation is so far off center of the dipper boom that it is difficult to operate in close quarter conditions, such as down in holes.
A further disadvantage of most known attachments is the absence of a horizontal edge on the attachments to work in cooperation with the teeth or edge of digging buckets. This edge is very important in handling many materials such as pipe or fence posts in vertical position, removing and handling sod, maneuvering and placing stone for rip-rap operations, and a wide variety of jobs that would be difficult without the horizontal edge.